With this increase in symptoms, past age 50, we can not call this IBS.
A colonoscopy was indicated for screening at age 50, but with these bowel changes, is now mandatory.
It is not a situation where it is correct to say "you might have to have your stool checked for blood."
That should have been done yearly, but now, blood or not, colonoscopy. It is not true that probiotics do not cause gas. They do in some people. And, if you have small bowel overgrowth, probiotics typically make symptoms worse.
In fact, neither a GP or a typical specialist will do sensitivity testing for foods, as opposed to conventional allergy testing. For that [IgG testing] you need a specific type of doctor trained in this [functional medicine].
A hydrogen breath test can indicated if there is small bowel overgrowth.
Finally, 3 stool samples should be sent of parasite analysis, as giardia can be chronic, and the main symptom in this case is gas.
Simethicone can alleviate gas temporarily, but addresses no underlying cause of gas. Also we have not reviewed your diet, which could also be a problem.
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